An enhancement-mode MOSFET class-AB output stage is shown in Figure P8.29. The threshold voltage of each transistor is \(V_{T N}=-V_{T P}=1 \mathrm{~V}\) and the conduction parameters of the output transistors are \(K_{n 1}=K_{p 2}=\) \(5 \mathrm{~mA} / \mathrm{V}^{2}\). Let \(I_{\text {Bias }}=200 \mu \mathrm{A}\).

(a) Determine \(K_{n 3}=K_{p 4}\) such that the quiescent drain currents in \(M_{1}\) and \(M_{2}\) are \(5 \mathrm{~mA}\).

(b) Using the results of part (a), find the small-signal voltage gain \(A_{v}=d v_{O} / d v_{I}\) evaluated at: (i) \(v_{O}=0\), and (ii) \(v_{O}=5 \mathrm{~V}\).

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Bias M3 VI M4 +12 V I M -01/0 R = M2 500 -12 V Figure P8.29